[00:51:45] [Server thread/ERROR]: Could not pass event PlayerQuitEvent to TheWalls v2.0.1
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:509) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:494) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.PlayerList.disconnect(PlayerList.java:334) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.PlayerConnection.a(PlayerConnection.java:738) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.ServerConnection.c(ServerConnection.java:77) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.MinecraftServer.v(MinecraftServer.java:734) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:289) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:584) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:490) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [serwer32899.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
Caused by: java.lang.NullPointerException
at java.util.concurrent.ConcurrentHashMap.hash(Unknown Source) ~[?:1.7.0_55]
at java.util.concurrent.ConcurrentHashMap.containsKey(Unknown Source) ~[?:1.7.0_55]
at net.cubecraftgames.walls.PlayerDisconnectListner.OnPlayerDisconnect(PlayerDisconnectListner.java:22) ~[?:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_55]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0_55]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0_55]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.7.0_55]
at org.bukkit